• 제목/요약/키워드: Field trapping

검색결과 134건 처리시간 0.025초

노지 고추재배지에 발생하는 총채벌레를 대상으로 methyl isonicotinate와 집합페로몬 혼합물을 이용한 고효율 대량유살 기술 (High Efficient Mass-trapping Technique using a Mixture of Methyl Isonicotinate and Aggregation Pheromone to Control the Thrips Infesting Hot Peppers in Open Field Conditions)

  • 김용균;진가현;박현제;김철영
    • 한국응용곤충학회지
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    • 제62권4호
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    • pp.245-253
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    • 2023
  • 대량유살 기술을 통한 총채벌레 방제 기술이 시설 고추재배지를 중심으로 개발되었다. 이 기술의 핵심 요인은 효과적 유인제 개발에 있다. 집합페로몬에 의존하였던 유인전략은 노지 재배지에서는 뚜렷한 효과를 보이지 않았다. 따라서 본 연구는 노지 고추재배지에서 총채벌레의 대량 유살을 위해 새로운 유인물질의 추가가 필요하였다. 또한 노지재배지에서 집합페로몬의 유인력 감소 원인을 규명할 필요가 있었다. 새로운 유인물질로서 methyl isonicotinate (MIN)이 제시되었고, 이 물질이 실내 유인행동분석을 통해 총채벌레에 대한 자체 유인력은 물론이고 집합페로몬과 협력효과를 보였다. 이를 바탕으로 집합페로몬과 혼합물 형태로 노지 고추재배지에서 분석한 결과 총채벌레의 포획밀도를 증가시켰다. 특히 이러한 증가는 꽃노랑총채벌레(Frankliniella occidentalis)에서 뚜렷하게 나타났다. 유인트랩에 집합페로몬의 함량 증가는 노지 고추재배지에서 꽃노랑총채벌레는 물론이고 다른 총채벌레류의 포획밀도를 뚜렷하게 증가시켰다. 본 연구는 집합페로몬 유인력이 시설재배지와 노지재배지 사이에서 차이가 있으며, 노지 재배지의 경우 효과적 유인력을 발휘하기 위해서는 더욱 많은 집합페로몬 함량을 요구한다는 것을 밝혔다. 또한 본 연구는 집합페로몬에 MIN을 추가하여 꽃노랑총채벌레에 대한 고효율 유인제를 개발할 수 있는 기술을 제시한다.

Maxwell nanofluid flow through a heated vertical channel with peristalsis and magnetic field

  • Gharsseldien, Z.M.;Awaad, A.S.
    • Advances in nano research
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    • 제13권1호
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    • pp.77-86
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    • 2022
  • This paper studied the peristaltic transport of upper convected Maxwell nanofluid through a porous medium in a heated (isothermal) symmetric vertical channel. The nanofluid is assumed to be electrically conducting in the presence of a uniform magnetic field. These phenomena are modeled mathematically by a differential equations system by taking low Reynolds number and long-wavelength approximation, the yield differential equations have solved analytically. A suggested new technique to display and discuss the trapping phenomenon is presented. We discussed and analyzed the pumping characteristics, heat function, flow velocity and trapping phenomena which were illustrated graphically through a set of figures for various values of parameters of the problem. The numerical results show that, there are remarkable effects on the vertical velocity, pressure gradient and trapping phenomena with the thermal change of the walls.

FDTD 방법을 이용한 광집게의 포획 힘 계산 (Calculations of the Trapping Force of Optical Tweezers using FDTD Method)

  • 성승용;이용구
    • 한국광학회지
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    • 제19권1호
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    • pp.80-83
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    • 2008
  • 광집게는 매질보다 큰 굴절률을 가지는 마이크로 크기의 구형 유전체를 강하게 집속되는 레이저를 이용해서 포획하고 움직이는 도구이다. 본 논문에서는 FDTD 방법을 이용해서 포획 힘을 계산하고, 그 방법을 설명하였다. 강하게 집속되는 레이저는 nonparaxial Gaussian beam을 이용해서 표현하였으며, 레이저가 대상물체와 매질에서 진행하는 것은 FDTD 방법을 이용해서 시뮬레이션 하였다. 레이저를 계산공간 전체에서 해석적으로 표현하기 위해서 scattered field formulation을 이용하였다. FDTD 방법을 이용해서 대상물체의 안팎의 전자기장을 시뮬레이션하고, 그 결과를 이용해서 Maxwell's stress tensor에 기반하여 포획 힘을 계산하였다.

SC PMOSFET의 수평 전개 모델과 노쇠화 메카니즘 (Lateral Electric Field Model and Degradation Mechanism of surface-Channel PMOSFET's)

  • 양광선;박종태;김봉렬
    • 전자공학회논문지A
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    • 제31A권1호
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    • pp.54-60
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    • 1994
  • In this paper, we present the analytical models for the change of the lateral electric field distribution and the velocity saturation region length with the electron trapping of stressed SC-PMOSFET in the saturation region. To derive the hot-electron-induced lateral electric field of stressed SC-PMOSFET. Ko's pseudo two dimensional box model in the saturation region which illustrates the analysis of the velocity saturation region is modified under the condition of electron trapping in the oxide near the drain region. From the results, we have the following lateral electric field in the y-direction, that is, E(y) ES1satT.cosh(y/l) qNS1tT.sinh(y/l)/lCox. It is shown that the trapped electrons influence the field in the drain region. decreasing the lateral electric field. Calculated velocity saturaion length increases with the trapped electrons. increasing the drain current of stressed SCPMOSFET. This results well explain the HEIP phenomenon of PMOSFET's.

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Comparative Trapping Efficiency of Five Different Blends of the Two Sex Pheromone Components in Dichocrocis punctiferalis (Lepidoptera: Pyralidae) at Chestnut Orchards in Korea

  • Choi, Kwang Sik;Choi, Won Il;Lee, Chong Kyu;Kim, Young Jae;Jeon, Mun Jang;Shin, Sang Chul
    • 한국산림과학회지
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    • 제97권5호
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    • pp.555-558
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    • 2008
  • Trapping efficiency of various sex pheromone blends of the peach pyralid moth, Dichocrocis punctiferalis was compared by field study to develop monitoring system with its sex pheromone at chestnut orchards in Korea. Five candidates of the sex pheromone blends used for the field trapping of D. punctiferalis males were 70:30, 75:25, 80:20, 85:15 and 90:10 mixture of (E)-10-hexadecenyl aldehyde (E10-16:Al) and (Z)-10-hexadecenyl aldehyde (Z10-16:Al). All lures were treated with 1 or 2 mg of each blends. During 2 years of field survey, the 75:25 blend was usually the most effective in attracting males among 5 blends tested. For the 2nd generation, the best capturing activity for D. punctiferalis male was observed by lure with 75:25 blend. Both 90:10 and 75:25 blends showed highest efficiency for the 3rd generation. In most cases. lures treated with 1 mg of blend caught more male moths than these treated with 2 mg of blend.

유기전계효과 트랜지스터의 반도체/고분자절연체 계면에 발생하는 비가역적 전하트래핑에 관한 연구 (Irreversible Charge Trapping at the Semiconductor/Polymer Interface of Organic Field-Effect Transistors)

  • 임재민;최현호
    • 접착 및 계면
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    • 제21권4호
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    • pp.129-134
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    • 2020
  • 공액분자반도체와 고분자절연체 계면에서 전하트래핑을 이해하는 것은 장시간 구동가능한 안정성 높은 유기전계효과 트랜지스터(이하 유기트랜지스터) 개발을 위해 중요하다. 본 연구에서는 다양한 분자량의 고분자절연체를 이용한 유기트랜지스터의 전하이동 특성을 평가하였다. Polymethyl methacrylate (PMMA) 표면 위에 적층된 펜타센 공액반도체의 모폴로지와 결정성은 PMMA 분자량에 무관함이 나타났다. 그 결과 트랜지스터 소자의 초기 트랜스퍼 곡선과 전하이동도는 분자량에 상관없었다. 하지만, 적정한 상대습도 환경에서 소자에 바이어스가 인가되었을 경우, 바이어스 스트레스 효과로 불리는 드레인전류 감소와 트랜스퍼 곡선 이동은 PMMA 분자량이 감소할수록 증대됨이 관찰되었다(분자량 효과). 분자량 효과에 의한 전하트래핑은 회복이 매우 어려운 비가역적인 과정임을 밝혀 내었다. 이러한 분자량 효과는 PMMA 존재하는 고분자사슬 말단의 밀도 변화에 의한 것으로 판단된다. 즉, PMMA 고분자사슬 말단이 가지는 자유부피가 전하트랩으로 작용하여 분자량에 민감한 바이어스 스트레스 효과를 일으킨 것으로 판단된다.

Formation of Magnetic Structures for Trapping of Breast Cancer Cell

  • Alaa Alasadi;Ali Ghanim Gatea Al Rubaye
    • 한국재료학회지
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    • 제34권3호
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    • pp.144-151
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    • 2024
  • This work focuses on the fabrication of excellent magnetic structures for trapping breast cancer cells. Micromagnetic structures were patterned for trapping cancer cells by depositing 30 nm of permalloy on a silicon substrate. These structures were designed and fabricated using two fabrication techniques: electron beam lithography and laser direct writing. Two types of magnetic structures, rectangular wire and zig-zagged wire, were created on a silicon substrate. The length of each rectangular wire and each straight line of zig-zagged wire was 150 ㎛ with a range of widths from 1 to 15 ㎛ for rectangular and 1, 5, 10 and 15 ㎛ for zigzag, respectively. The magnetic structures showed good responses to the applied magnetic field despite adding layers of silicon nitride and polyethylene glycol. The results showed that Si + Si3N4 + PEG exhibited the best adhesion of cells to the surface, followed by Si + Py + Si3N4 + PEG. concentration of 5-6 with permalloy indicates that this layer affected silicon nitride in the presence of Polyethylene glycolPEG.

고분자내 케리아의 트랍핑 현상에 관한 연구 (The Study on Trapping Phenomena of Charge Carrier in Polymer)

  • 이덕출
    • 전기의세계
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    • 제26권4호
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    • pp.68-72
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    • 1977
  • The main purpose of this paper is to study on the nature of the traps in polymer. The polyethlene is typical of polymer material as to be selected for a sample. The current I$_{th}$ are obtained with an small external bias voltage from high density polyethylene which have been treated by the high-field application. Two peaks, P$_{1}$ and P$_{2}$ with maxima near 85.deg. C, respectively, appeared on the current I$_{th}$ spectrum. From the results of experiment, It is clear that The current I$_{th}$ arises from the drift, under the external field, of carriers released from the trap sites by the heating and the trap is surrounded by a potential barrier and trapping proceeds during the high-field treatment. The obtained results can suggest that polyethylene contains trap sites which have an important role in the electrical conduction and breakdown of polymeric materials.rials.

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Metal-$Al_2O_3$-p Si$의 MOS 구조에 있어서 고전계에의한 Carrier주입과 트랩에 관한 연구 (A Study on Carrier Injection and Trapping by the High Field for MOS(Metal-$Al_2O_3$-p Si$) Structure)

  • 박성희;성만영
    • 대한전자공학회논문지
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    • 제24권1호
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    • pp.102-109
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    • 1987
  • This study is carrier out to investigate the carrier injection and the characteristics of trapping for the CVD deposited Al2O3 film on Si substrates. Samples used are metal -Al2O3-Si Structure in which metal field plates are used with Aluminium or God. Canier injection and trapping, which result in flat band voltalge shift, occur at fields as low as 1~2 MV/cm. An approximate method is proposed for computing the location of the centroid of the trapped electrons in this paper. Results show that carriers are trapped near the injecting interface at fields less than about 5MV/cm. Because of continued charging, a steady state can not be reached. Therefore the unique I-V curve is obtained when the traps are initially empty. By utilization of applied voltage on each point of the fresh device sample, it is measured the I-V surves for two polarities of applied voltage. The current densities observed in the Al2O3 films are much larger than those obtained in SiO2.

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Newly Synthesized Silicon Quantum Dot-Polystyrene Nanocomposite Having Thermally Robust Positive Charge Trapping

  • Dung, Mai Xuan;Choi, Jin-Kyu;Jeong, Hyun-Dam
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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    • pp.221-221
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    • 2013
  • Striving to replace the well known silicon nanocrystals embedded in oxides with solution-processable charge-trapping materials has been debated because of large scale and cost effective demands. Herein, a silicon quantum dot-polystyrene nanocomposite (SiQD-PS NC) was synthesized by postfunctionalization of hydrogen-terminated silicon quantum dots (H-SiQDs) with styrene using a thermally induced surface-initiated polymerization approach. The NC contains two miscible components: PS and SiQD@PS, which respectively are polystyrene and polystyrene chains-capped SiQDs. Spin-coated films of the nanocomposite on various substrate were thermally annealed at different temperatures and subsequently used to construct metal-insulator-semiconductor (MIS) devices and thin film field effect transistors (TFTs) having a structure p-$S^{++}$/$SiO_2$/NC/pentacene/Au source-drain. C-V curves obtained from the MIS devices exhibit a well-defined counterclockwise hysteresis with negative fat band shifts, which was stable over a wide range of curing temperature ($50{\sim}250^{\circ}C$. The positive charge trapping capability of the NC originates from the spherical potential well structure of the SiQD@PS component while the strong chemical bonding between SiQDs and polystyrene chains accounts for the thermal stability of the charge trapping property. The transfer curve of the transistor was controllably shifted to the negative direction by chaining applied gate voltage. Thereby, this newly synthesized and solution processable SiQD-PS nanocomposite is applicable as charge trapping materials for TFT based memory devices.

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